Indian scientists unravel secrets behind hospital infections

Giving an insight into how and why hospital-borne infections spread, scientists at the Indian Institute of Chemical Biology here have said bacteria play hide and seek with the human body's defence cells by surrounding themselves with sugar molecules to fool cells.

Researchers led by scientist Chitra Mandal have unravelled the sinister mechanism by which the bacteria that goes by the name of Pseudomonas aeruginosa, responsible for hospital-borne infections, invades the human body, eludes the neutrophils (immune cells responsible for defence) and establishes infection.

Pseudomonas aeruginosa is a rod shaped, airborne disease-causing bacterium, a pathogen commonly found in patients with low immunity and in patients who have been hospitalised.

Besides hospital-borne infections like pneumonia, Pseudomonas aeruginosa is also responsible for urinary tract infections (UTIs), respiratory infections and other afflictions.

These infections can lead to complications and even death.

"Be it burns, wounds, you name it, this bug is present," Mandal, head of the Cancer Biology and Inflammatory Disorder Division, Council of Scientific & Industrial Research (CSIR)-Indian Institute of Chemical Biology, told IANS.

Neutrophils, which form the first line of defence, are the most abundant class of white blood cells that help the body to fight infection.

They protect the body against invading pathogens like bacteria and parasites and remove wastes, foreign substances and other cells in a process where they eat or engulf these particles.

According to the study published in the Journal of Leukocyte Biology in 2012, as part of the evasive tactics used by the bacterium, it first picks up specific sugar molecules called sialic acid (sias) from its environment (the human body in this case) and surrounds itself with it.

Highlighting the importance of the research, microbiologist Nemai Bhattacharya of the School of Tropical Medicine told IANS: "These bacteria are difficult to deal with because of their capability to resist common antibiotics. They have been found to grow in antiseptic solutions as well. Studies such as the one done by the scientists provide valuable insights into the bacterium's activities."